Local support

Despite unprecedented criticism on Brunei's active social media, the move appears to enjoy broad community support, especially among Muslim ethnic Malays, who make up about 70 per cent of the population.

The UN's human rights office and various international rights and legal activist groups also have condemned the move as out of step with modern society.

Brunei is the first country in East or South-East Asia to introduce a sharia penal code on a national level, joining several mostly Middle Eastern countries like Saudi Arabia and Iran.

Attorney general Hayati Salleh sought to ease concerns over the code's implementation, stressing that sharia cases will face high burdens of proof before the tough penalties are imposed.

"It is crucial that we, and the international community, understand these distinctions and not focus solely on the punishments but rather, on the evidence-gathering process that is complicated and strict," she said.

The monarch's wealth - estimated three years ago at $US20 billion by Forbes magazine - is legendary with reports of a vast collection of luxury vehicles and huge palaces.

The monarchy was deeply embarrassed by a sensational family feud between Sultan Hassanal and his younger brother Jefri Bolkiah over the latter's alleged embezzlement of $15 billion during his tenure as finance minister in the 1990s.